Packaging for electronics in downhole assemblies

Abstract

A downhole device configured to be inserted into a borehole includes a device body having an outer surface and a recess formed in the outer surface and a cover covering the recess to form a first cavity, the cover forming a fluid-tight seal with the device body. The device includes at least one shock-absorber configured to support an electrical module within the first cavity, the at least one shock-absorber extending between a base of the cavity and an inner surface of the cover opposite the base. The device also includes a vibration-damping layer located on at least one of the base of the cavity and the inner surface of the cover, the vibration-damping layer configured to be in contact with a surface of the electrical module to dampen vibration of the electrical module.

1 . A downhole device configured to be inserted into a borehole, the downhole device comprising:
 a device body having an outer surface and a recess formed in the outer surface;   a cover covering the recess to form a first cavity, the cover forming a fluid-tight seal with the device body;   at least one shock-absorber configured to support an electrical module within the first cavity, the at least one shock-absorber extending between a base of the cavity and an inner surface of the cover opposite the base; and   a vibration-damping layer located on at least one of the base of the cavity and the inner surface of the cover, the vibration-damping layer configured to be in contact with a surface of the electrical module to dampen vibration of the electrical module.   
     
     
         2 . The downhole device of  claim 1 , wherein the downhole device is a segment of a downhole assembly, and
 the device body is a collar body defining a second cavity extending end-to-end through the collar body.   
     
     
         3 . The downhole device of  claim 2 , wherein the second cavity is configured to have a fluid flow therethrough, and the vibration-damping layer is made of a temperature-transmitting material configured to transmit heat from the electrical module, through the vibration-damping layer and the collar body, to the fluid. 
     
     
         4 . The downhole device of  claim 1 , wherein the downhole device is a downhole probe configured to be inserted into the borehole to obtain measurements of characteristics of one or more of the borehole, fluid in the borehole, and an earth formation. 
     
     
         5 . The downhole device of  claim 1 , wherein the at least one shock-absorber includes a first shock-absorber configured to support a first end of the electrical module and a second shock-absorber configured to support a second end of the electrical module opposite the first end. 
     
     
         6 . The downhole device of  claim 5 , wherein the vibration-damping layer is located between the first shock-absorber and the second shock-absorber. 
     
     
         7 . The downhole device of  claim 1 , wherein the at least one shock-absorber is configured to maintain the electrical module stationary within the first cavity by contacting a first surface of the electrical module facing the base of the first cavity, a second surface of the electrical module opposite the first surface and facing the cover. 
     
     
         8 . The downhole device of  claim 7 , wherein the at least one shock-absorber is configured to maintain the electrical module stationary within the first cavity by contacting each surface of the electrical module. 
     
     
         9 . The downhole device of  claim 1 , wherein the at least one shock-absorber is configured to maintain the electrical module stationary within the first cavity without screws. 
     
     
         10 . The downhole device of  claim 1 , wherein the shock-absorber is a pre-formed elastomer. 
     
     
         11 . The downhole device of  claim 1 , wherein the vibration-damping layer is made of a viscoelastic material. 
     
     
         12 . The downhole device of  claim 1 , wherein the cover is a sleeve covering an entire outer radial surface of the device body. 
     
     
         13 . A downhole assembly having a plurality of downhole segments for being inserted in a borehole, the downhole assembly comprising:
 a first downhole segment, among the plurality of downhole segments, having a recess in an outer surface of a collar body defining a first cavity and the collar body defining a second cavity extending end-to-end through the collar body, the first downhole segment including a cover covering the first cavity to sealingly enclose the first cavity;   at least one shock-absorber configured to support an electrical module within the first cavity, the at least one shock-absorber extending between a base of the first cavity and an inner surface of the cover; and   a vibration-damping layer located on the base of the first cavity and configured to be in contact with a surface of the electrical module to damp vibration of the electrical module.   
     
     
         14 . The downhole assembly of  claim 13 , wherein the at least one shock-absorber includes a first shock-absorber configured to support a first end of the electrical module and a second shock-absorber configured to support a second end of the electrical module opposite the first end. 
     
     
         15 . The downhole assembly of  claim 14 , wherein the vibration-damping layer is located between the first shock-absorber and the second shock-absorber. 
     
     
         16 . The downhole assembly of  claim 13 , wherein the plurality of downhole segments include a channel configured to have fluid flow therethrough, the second cavity being part of the channel, the vibration-damping layer being made of a temperature-transmitting material for transmitting heat from the electrical module, through the vibration-damping layer and the collar body to the fluid. 
     
     
         17 . The downhole assembly of  claim 13 , wherein the at least one shock-absorber is configured to maintain the electrical module stationary within the first cavity by contacting each surface of the electrical module. 
     
     
         18 . The downhole assembly of  claim 13 , wherein the at least one shock-absorber is configured to maintain the electrical module stationary within the first cavity without screws. 
     
     
         19 . The downhole assembly of  claim 13 , wherein the shock-absorber is a pre-formed elastomer. 
     
     
         20 . The downhole assembly of  claim 13 , wherein the vibration-damping layer is made of a viscoelastic material.